These new ThreatWerx 30 Cal Simulated Fire (Sim-Fire) Guns. ThreatWerx supplies most of the guns to the film industry among others ThreatWerx has created guns mounted on the Batmobile and in the Transformers movies. They are copies of the M1919 Browning Machine Gun and fire a mixture of Oxygen and Acetylene. We ordered these a few years ago for a project we never completed. They come complete with bottles and everything needed to fire. If you never saw these in action, pull them up on the internet, you will be amazed. They are designed to be solid mounted but can easily be converted over to a Tripod Mount. We paid $4000 each for these in 2015, they are $5899 each now, buy these for $2500 each